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Title Charge and isospin fluctuations in a non-ideal pion gas with dynamically fixed particle number Author info Evgeni E. Kolomeitsev ... [et al.] Author Kolomeitsev Evgeni E. 1970- (34%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (33%)
Borisov Maxim E. (33%)
Source document The European Physical Journal A : Hadrons and Nuclei. Vol. 57, no. 4 (2021), pp. [1-29]. - Berlin : Springer, 2021 Keywords Bose-Einsteinova kondenzácia - Bose-Einstein condensation heavy ion collisions Form. Descr. články - journal articles Language English Country Germany Public work category ADC No. of Archival Copy 49947 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika 
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Title Particle number fluctuations in a non-ideal pion gas Author info Evgeni E. Kolomeitsev, Maxim E. Borisov, Dmitry N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (98%) UMBFP06 - Katedra fyziky
Co-authors Borisov Maxim E. (1%)
Voskresensky Dmitri (1%)
Source document 6th international conference on new frontiers in physics (ICNFP 2017). Pp. [1-7]. - Les Ulis : Édition Diffusion Presse Sciences, 2018 ; International conference on new frontiers in physics (ICNFP 2017) medzinárodná konferencia Note Príspevok je evidovaný v databáze Scopus. Keywords particle number fluctuations pion gas particle physics Language English Country France systematics 53 Annotation We consider a non-ideal hot pion gas with the dynamically fixed number of particles in the model with the lambda-phi^4 interaction. The effective Lagrangian for the description of such a system is obtained by dropping the terms responsible for the change of the total particle number. Within the self-consistent Hartree approximation, we compute the effective pion mass, thermodynamic characteristics of the system and identify a critical point of the induced Bose-Einstein condensation when the pion chemical potential reaches the value of the effective pion mass. The normalized variance, skewness, and kurtosis of the particle number distributions are calculated. We demonstrate that all these characteristics remain finite at the critical point of the Bose-Einstein condensation. This is due to the non-perturbative account of the interaction and is in contrast to the ideal-gas case URL Link na zdrojový dokument Public work category AFC No. of Archival Copy 43933 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ 
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Title Fluctuations in non-ideal pion gas with dynamically fixed particle number Author info E. E. Kolomeitsev, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (50%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (50%)
Source document Nuclear Physics A. Vol. 973, (2018), pp. 89-103. - Amsterdam : Elsevier B.V., 2018 Keywords heavy ion collisions fluctuations Hartree approximation Bose-Einsteinova kondenzácia - Bose-Einstein condensation Language English Country Netherlands systematics 53 Annotation We consider a non-ideal hot pion gas with the dynamically fixed number of particles in the model with the λφ4interaction. The effective Lagrangian for the description of such a system is obtained after dropping the terms responsible for the change of the total particle number. Reactions π+π−↔π0π0, which deter-mine the isospin balance of the medium, are permitted. Within the self-consistent Hartree approximation we compute the effective pion mass, thermodynamic characteristics of the system and the variance of the particle number at temperatures above the critical point of the induced Bose–Einstein condensation when the pion chemical potential reaches the value of the effective pion mass. We analyze conditions for the con-densate formation in the process of thermalization of an initially non-equilibrium pion gas. The normalized variance of the particle number increases with a temperature decrease but remains finite in the critical point of the Bose–Einstein condensation. This is due to the non-perturbative account of the interaction and is in contrast to the ideal-gas case. In the kinetic regime of the condensate formation the variance is shown to stay finite also URL Link na plný text Public work category ADC No. of Archival Copy 43902 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Charged rho-meson condensation in neutron stars Author info Evgeni E. Kolomeitsev, K. A. Maslov ... [et al.] Author Kolomeitsev Evgeni E. 1970- (34%) UMBFP06 - Katedra fyziky
Co-authors Maslov K. A. (33%)
Voskresensky Dmitri (33%)
Source document Nuclear Physics A. Vol. 970, (2018), pp. 291-315. - Amsterdam : Elsevier B.V., 2018 Keywords neutron stars equation of state condensation Language English Country Netherlands systematics 53 Annotation We extend relativistic mean-field models with hadron masses and meson–baryon coupling constants dependent on the scalar field σ, including hyperons and (1232)baryons, to incorporate a possibility of the charged ρmeson condensation in neutron star matter. The influence of the ρ−condensation on the equation of state proves to be strongly model dependent. In our models of one type (KVORcut-based ones) the ρ−condensation arises by a second-order phase transition above a critical density and the maximum value of the neutron star mass diminishes only slightly. The matter composition changes more significantly. In our models of other type (MKVOR*-based ones), if the system is considered at fixed density, the ρ−condensation arises by a second-order phase transition at the baryon density n =n(II)c,ρand at a slightly higher density n =n(I)c,ρthere occurs a first-order phase transition. In a neutron star matter starting with a density n <n(II)c,ρthere appears a region of a mixed phase, or the system is described by Maxwell construction, that results in a substantial decrease of the value of the maximum neutron star mass. Nevertheless in the models under consideration the observational constraint on the maximum neutron star mass is fulfilled. Besides, in MKVOR*-based models the appearance of the ρ−condensate is accompanied by a strong rearrangement of the matter composition. Dependence of the results on a choice of the ρmeson scaling functions for the effective ρmeson mass and coupling constants is also investigated URL Link na plný text Public work category ADC No. of Archival Copy 43905 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title On cooling of neutron stars with a stiff equation of state including hyperons Author info Hovik Grigorian, Evgeni E. Kolomeitsev ... [et al.] Author Grigorian Hovik (25%)
Co-authors Kolomeitsev Evgeni E. 1970- (25%) UMBFP06 - Katedra fyziky
Maslov Konstantin A. (25%)
Voskresensky Dmitri (25%)
Source document Universe. Vol. 4, no. 2 (2018), pp. 1-6. - Basel : Multidisciplinary Digital Publishing Institute, 2018 Keywords equation of state neutron stars neutrína - neutrinos Language English Country Switzerland systematics 53 Annotation Exploiting a stiff equation of state of the relativistic mean-field model MKVORHf with sigma-scaled hadron effective masses and couplings, including hyperons, we demonstrate that the existing neutron-star cooling data can be appropriately described within “the nuclear medium cooling scenario” under the assumption that different sources have different masses URL Link na zdrojový dokument Public work category ADM No. of Archival Copy 43911 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Charged rho meson condensate in neutron stars within RMF models Author info Konstantin A. Maslov, Evgeni E. Kolomeitsev, Dmitry N. Voskresensky Author Maslov Konstantin A. (34%)
Co-authors Kolomeitsev Evgeni E. 1970- (33%) UMBFP06 - Katedra fyziky
Voskresensky Dmitri (33%)
Source document Universe. Vol. 4, no. 1 (2018), pp. 1-8. - Basel : Multidisciplinary Digital Publishing Institute, 2018 ; Compact stars in the QCD Phase Diagram medzinárodná konferencia Keywords neutron stars equation of state rho meson condensation maximum mass Delta resonances Language English Country Switzerland systematics 53 Annotation Knowledge of the equation of state (EoS) of cold and dense baryonic matter is essential for the description of properties of neutron stars (NSs). With an increase of the density, new baryon species can appear in NS matter, as well as various meson condensates. In previous works, we developed relativistic mean-field (RMF) models with hyperons and Δ -isobars, which passed the majority of known experimental constraints, including the existence of a 2 M ⊙ neutron star. In this contribution, we present results of the inclusion of ρ − -meson condensation into these models. We have shown that, in one class of the models (so-called KVOR-based models, in which the additional stiffening procedure is introduced in the isoscalar sector), the condensation gives only a small contribution to the EoS. In another class of the models (MKVOR-based models with additional stiffening in isovector sector), the condensation can lead to a first-order phase transition and a substantial decrease of the NS mass. Nevertheless, in all resulting models, the condensation does not spoil the description of the experimental constraints URL https://www.mdpi.com/2218-1997/4/1/1 Public work category AFC No. of Archival Copy 43907 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title The effect of inclusion of delta resonances in relativistic mean-field model with scaled hadron masses and coupling constants Author info K. A. Maslov, E. E. Kolomeitsev, D. N. Voskresensky Author Maslov Konstantin A. (1%)
Co-authors Kolomeitsev Evgeni E. 1970- (98%) UMBFP06 - Katedra fyziky
Voskresensky Dmitri (1%)
Source document Journal of Physics: Conference Series. Vol. 798 (2017), pp. 1-5. - Bristol : IOP Publishing, 2017 ; International conference on particle physics and astrophysics ICPPA 2017 medzinárodná konferencia Keywords astrofyzika - astrophysics neutron stars relativita - relativity Language English Country Great Britian systematics 53 Annotation © Published under licence by IOP Publishing Ltd.Knowledge of the equation of state of the baryon matter plays a decisive role in the description of neutron stars. With an increase of the baryon density the filling of Fermi seas of hyperons and Δ isobars becomes possible. Their inclusion into standard relativistic mean-field models results in a strong softening of the equation of state and a lowering of the maximum neutron star mass below the measured values. We extend a relativistic mean-field model with scaled hadron masses and coupling constants developed in our previous works and take into account now not only hyperons but also the Δ isobars. We analyze available empirical information to put constraints on coupling constants of Δs to mesonic mean fields. We show that the resulting equation of state satisfies majority of presently known experimental constraints. Public work category AFC No. of Archival Copy 39068 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Zero-Sound Condensate in a Fermi Liquid Author info E. E. Kolomeitsev, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (99%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (1%)
Source document Physics of Particles and Nuclei. Vol. 48, no. 6 (2017), pp. 897-899. - New York : Pleiades Publishing, 2017 ; The International Session-Conference of SNP PSD RAS “Physics of Fundamental Interactions” konferencia Keywords Fermi liquid nuclear matter sound modes Language English Country United States of America systematics 53 Annotation We consider a normal Fermi liquid with a local scalar interaction given by the Landau parameter f_0. The system becomes unstable for f_0<-1 against a growth of scalar-mode excitations (Pomeranchuk instability). We show that the instability may be tamed by the formation of a static Bose condensate of the scalar modes. We study a possible reconstruction of the isospin-symmetric nuclear matter owing to the appearance of the condensate. Possibility of a novel metastable state at subnuclear densities is demonstrated Public work category ADC No. of Archival Copy 40850 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
File name Downloaded Size Comment 40850 16 213.6 KB Title Condensate of excitations in moving superfluids Author info E. E. Kolomeitsev, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (99%) UMBFP06 - Katedra fyziky
Co-authors Voskresensky Dmitri (1%)
Source document Progress of Theoretical and Experimental Physics. No. 2 (2017), pp. [1-14]. - [Oxford] : Oxford University Press, 2017 Keywords nuclear matter Fermi liquid Language English Country United States of America systematics 53 Annotation The possibility of the condensation of excitations with non-zero momentum in rectilinearly moving and rotating superfluid bosonic and fermionic (with Cooper pairing) media is considered in terms of a phenomenological order-parameter functional at zero and non-zero temperature. The results might be applicable to the description of bosonic systems like superfluid He-4, ultracold atomic Bose gases, charged pion and kaon condensates in rotating neutron stars, and various superconducting fermionic systems with pairing, like proton and color-superconducting components in compact stars, metallic superconductors, and neutral fermionic systems with pairing, like the neutron component in compact stars and ultracold atomic Fermi gases. The order parameters of the "mother" condensate in the superfluid and the new condensate of excitations, corresponding energy gains, critical temperatures, and critical velocities are found. Public work category ADC No. of Archival Copy 39051 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised
Title Delta isobars in relativistic mean-field models with sigma-scaled hadron masses and couplings Author info E. E. Kolomeitsev, K. A. Maslov, D. N. Voskresensky Author Kolomeitsev Evgeni E. 1970- (98%) UMBFP06 - Katedra fyziky
Co-authors Maslov Konstantin A. (1%)
Voskresensky Dmitri (1%)
Source document Nuclear Physics A. Vol. 961 (2017), pp. 106-141. - Amsterdam : Elsevier B.V., 2017 Keywords neutron stars equation of state heavy ion collisions Language English Country Netherlands systematics 53 Annotation We extend the relativistic mean-field models with hadron masses and meson-baryon coupling constants dependent on the scalar sigma field, studied previously to incorporate Delta(1232) baryons. Available empirical information is analyzed to put constraints on the couplings of Delta s with meson fields. Conditions for the appearance of Delta s are studied. We demonstrate that with inclusion of the Delta s our equations of state continue to fulfill majority of known empirical constraints including the pressure-density constraint from heavy-ion collisions, the constraint on the maximum mass of the neutron stars, the direct Urea and the gravitational baryon mass ratio constraints. (C) 2017 Elsevier B.V. All rights reserved. Public work category ADC No. of Archival Copy 39909 Catal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Database xpca - PUBLIKAČNÁ ČINNOSŤ References PERIODIKÁ-Súborný záznam periodika unrecognised